diff --git a/rust/arrow/src/array/builder.rs b/rust/arrow/src/array/builder.rs
index b0b97c2210740..b647ae1eac813 100644
--- a/rust/arrow/src/array/builder.rs
+++ b/rust/arrow/src/array/builder.rs
@@ -705,7 +705,7 @@ mod tests {
         assert_eq!(0, b.len());
         assert_eq!(16, b.capacity());
         let a = b.finish();
-        assert_eq!(0, a.len());
+        assert_eq!(64, a.len());
     }
 
     #[test]
@@ -713,7 +713,7 @@ mod tests {
         let mut b = Int32BufferBuilder::new(0);
         b.append(123).unwrap();
         let a = b.finish();
-        assert_eq!(4, a.len());
+        assert_eq!(64, a.len());
     }
 
     #[test]
@@ -724,7 +724,7 @@ mod tests {
         }
         assert_eq!(16, b.capacity());
         let a = b.finish();
-        assert_eq!(20, a.len());
+        assert_eq!(64, a.len()); // 16 * size_of(i32)
     }
 
     #[test]
@@ -736,7 +736,7 @@ mod tests {
         }
         assert_eq!(32, b.capacity());
         let a = b.finish();
-        assert_eq!(80, a.len());
+        assert_eq!(128, a.len()); // 32 * size_of(i32)
     }
 
     #[test]
@@ -747,7 +747,7 @@ mod tests {
             b.append(i).unwrap();
         }
         let mut a = b.finish();
-        assert_eq!(40, a.len());
+        assert_eq!(64, a.len());
         assert_eq!(0, b.len());
         assert_eq!(0, b.capacity());
 
@@ -757,7 +757,7 @@ mod tests {
         }
         assert_eq!(32, b.capacity());
         a = b.finish();
-        assert_eq!(80, a.len());
+        assert_eq!(128, a.len());
     }
 
     #[test]
@@ -783,12 +783,12 @@ mod tests {
         b.append_slice("Hello, ".as_bytes()).unwrap();
         b.append_slice("World!".as_bytes()).unwrap();
         let buffer = b.finish();
-        assert_eq!(13, buffer.len());
+        assert_eq!(64, buffer.len());
 
         let mut b = Int32BufferBuilder::new(0);
         b.append_slice(&[32, 54]).unwrap();
         let buffer = b.finish();
-        assert_eq!(8, buffer.len());
+        assert_eq!(64, buffer.len());
     }
 
     #[test]
@@ -801,14 +801,14 @@ mod tests {
         assert_eq!(4, b.len());
         assert_eq!(512, b.capacity());
         let buffer = b.finish();
-        assert_eq!(1, buffer.len());
+        assert_eq!(64, buffer.len());
 
         let mut b = BooleanBufferBuilder::new(4);
         b.append_slice(&[false, true, false, true]).unwrap();
         assert_eq!(4, b.len());
         assert_eq!(512, b.capacity());
         let buffer = b.finish();
-        assert_eq!(1, buffer.len());
+        assert_eq!(64, buffer.len());
     }
 
     #[test]
@@ -819,7 +819,7 @@ mod tests {
         assert_eq!(4, b.len());
         assert_eq!(16, b.capacity());
         let buffer = b.finish();
-        assert_eq!(16, buffer.len());
+        assert_eq!(64, buffer.len());
     }
 
     #[test]
diff --git a/rust/arrow/src/array/data.rs b/rust/arrow/src/array/data.rs
index ac6ad4fa9ce56..48055b78ea781 100644
--- a/rust/arrow/src/array/data.rs
+++ b/rust/arrow/src/array/data.rs
@@ -275,7 +275,7 @@ mod tests {
         assert_eq!(10, arr_data.null_count());
         assert_eq!(5, arr_data.offset());
         assert_eq!(1, arr_data.buffers().len());
-        assert_eq!(&[0, 1, 2, 3], arr_data.buffers()[0].data());
+        assert_eq!([0, 1, 2, 3], arr_data.buffers()[0].data()[..4]);
         assert_eq!(1, arr_data.child_data().len());
         assert_eq!(child_arr_data, arr_data.child_data()[0]);
     }
diff --git a/rust/arrow/src/buffer.rs b/rust/arrow/src/buffer.rs
index eea000fe5c28a..f4660d293f73d 100644
--- a/rust/arrow/src/buffer.rs
+++ b/rust/arrow/src/buffer.rs
@@ -178,7 +178,7 @@ impl<T: AsRef<[u8]>> From<T> for Buffer {
         unsafe {
             memory::memcpy(buffer, slice.as_ptr(), len);
         }
-        Buffer::from_raw_parts(buffer, len)
+        Buffer::from_raw_parts(buffer, capacity)
     }
 }
 
@@ -448,7 +448,7 @@ impl MutableBuffer {
     pub fn freeze(self) -> Buffer {
         let buffer_data = BufferData {
             ptr: self.data,
-            len: self.len,
+            len: self.capacity,
         };
         ::std::mem::forget(self);
         Buffer {
@@ -534,26 +534,26 @@ mod tests {
         assert!(buf.raw_data().is_null());
 
         let buf = Buffer::from(&[0, 1, 2, 3, 4]);
-        assert_eq!(5, buf.len());
+        assert_eq!(64, buf.len());
         assert!(!buf.raw_data().is_null());
-        assert_eq!(&[0, 1, 2, 3, 4], buf.data());
+        assert_eq!([0, 1, 2, 3, 4], buf.data()[..5]);
     }
 
     #[test]
     fn test_from_vec() {
         let buf = Buffer::from(&[0, 1, 2, 3, 4]);
-        assert_eq!(5, buf.len());
+        assert_eq!(64, buf.len());
         assert!(!buf.raw_data().is_null());
-        assert_eq!(&[0, 1, 2, 3, 4], buf.data());
+        assert_eq!([0, 1, 2, 3, 4], buf.data()[..5]);
     }
 
     #[test]
     fn test_copy() {
         let buf = Buffer::from(&[0, 1, 2, 3, 4]);
         let buf2 = buf.clone();
-        assert_eq!(5, buf2.len());
+        assert_eq!(64, buf2.len());
         assert!(!buf2.raw_data().is_null());
-        assert_eq!(&[0, 1, 2, 3, 4], buf2.data());
+        assert_eq!([0, 1, 2, 3, 4], buf2.data()[..5]);
     }
 
     #[test]
@@ -561,20 +561,17 @@ mod tests {
         let buf = Buffer::from(&[2, 4, 6, 8, 10]);
         let buf2 = buf.slice(2);
 
-        assert_eq!(&[6, 8, 10], buf2.data());
-        assert_eq!(3, buf2.len());
+        assert_eq!([6, 8, 10], buf2.data()[0..3]);
+        assert_eq!(62, buf2.len());
         assert_eq!(unsafe { buf.raw_data().offset(2) }, buf2.raw_data());
 
         let buf3 = buf2.slice(1);
-        assert_eq!(&[8, 10], buf3.data());
-        assert_eq!(2, buf3.len());
+        assert_eq!([8, 10], buf3.data()[..2]);
+        assert_eq!(61, buf3.len());
         assert_eq!(unsafe { buf.raw_data().offset(3) }, buf3.raw_data());
 
         let buf4 = buf.slice(5);
-        let empty_slice: [u8; 0] = [];
-        assert_eq!(empty_slice, buf4.data());
-        assert_eq!(0, buf4.len());
-        assert!(buf4.is_empty());
+        assert_eq!(59, buf4.len());
     }
 
     #[test]
@@ -583,7 +580,7 @@ mod tests {
     )]
     fn test_slice_offset_out_of_bound() {
         let buf = Buffer::from(&[2, 4, 6, 8, 10]);
-        buf.slice(6);
+        buf.slice(65);
     }
 
     #[test]
@@ -627,14 +624,15 @@ mod tests {
     #[test]
     fn test_bitwise_not() {
         let buf = Buffer::from([0b01101010]);
-        assert_eq!(Buffer::from([0b10010101]), !&buf);
+        assert_eq!(Buffer::from([0b10010101]).data()[..1], (!&buf).data()[..1]);
     }
 
     #[test]
     #[should_panic(expected = "Buffers must be the same size to apply Bitwise OR.")]
     fn test_buffer_bitand_different_sizes() {
-        let buf1 = Buffer::from([1_u8, 1_u8]);
-        let buf2 = Buffer::from([0b01001110]);
+        let size = memory::ALIGNMENT * 2;
+        let buf1 = Buffer::from_raw_parts(memory::allocate_aligned(size), size);
+        let buf2 = Buffer::from([0x00]);
         let _buf3 = (&buf1 | &buf2).unwrap();
     }
 
@@ -722,18 +720,22 @@ mod tests {
         buf.write("aaaa bbbb cccc dddd".as_bytes())
             .expect("write should be OK");
         assert_eq!(19, buf.len());
+        assert_eq!(64, buf.capacity());
         assert_eq!("aaaa bbbb cccc dddd".as_bytes(), buf.data());
 
         let immutable_buf = buf.freeze();
-        assert_eq!(19, immutable_buf.len());
-        assert_eq!("aaaa bbbb cccc dddd".as_bytes(), immutable_buf.data());
+        assert_eq!(64, immutable_buf.len());
+        assert_eq!(
+            "aaaa bbbb cccc dddd".as_bytes(),
+            &immutable_buf.data()[..19]
+        );
     }
 
     #[test]
     fn test_access_concurrently() {
         let buffer = Buffer::from(vec![1, 2, 3, 4, 5]);
         let buffer2 = buffer.clone();
-        assert_eq!(&[1, 2, 3, 4, 5], buffer.data());
+        assert_eq!([1, 2, 3, 4, 5], buffer.data()[..5]);
 
         let buffer_copy = thread::spawn(move || {
             // access buffer in another thread.
diff --git a/rust/arrow/src/memory.rs b/rust/arrow/src/memory.rs
index d73ddd11676c8..32c9f726b5fd0 100644
--- a/rust/arrow/src/memory.rs
+++ b/rust/arrow/src/memory.rs
@@ -26,7 +26,7 @@ pub const ALIGNMENT: usize = 64;
 pub fn allocate_aligned(size: usize) -> *mut u8 {
     unsafe {
         let layout = Layout::from_size_align_unchecked(size, ALIGNMENT);
-        ::std::alloc::alloc(layout)
+        ::std::alloc::alloc_zeroed(layout)
     }
 }
 
diff --git a/rust/arrow/src/tensor.rs b/rust/arrow/src/tensor.rs
index 5382ca19c8807..ef69e35165142 100644
--- a/rust/arrow/src/tensor.rs
+++ b/rust/arrow/src/tensor.rs
@@ -86,11 +86,6 @@ impl<'a, T: ArrowPrimitiveType> Tensor<'a, T> {
     ) -> Self {
         match &shape {
             None => {
-                assert_eq!(
-                    buffer.len(),
-                    mem::size_of::<T::Native>(),
-                    "underlying buffer should only contain a single tensor element"
-                );
                 assert_eq!(None, strides);
                 assert_eq!(None, names);
             }
@@ -192,7 +187,10 @@ impl<'a, T: ArrowPrimitiveType> Tensor<'a, T> {
 
     /// The total number of elements in the `Tensor`
     pub fn size(&self) -> usize {
-        (self.buffer.len() / mem::size_of::<T::Native>())
+        match self.shape {
+            None => 0,
+            Some(ref s) => s.iter().fold(1, |a, b| a * b),
+        }
     }
 
     /// Indicates if the data is laid out contiguously in memory
@@ -260,7 +258,7 @@ mod tests {
     fn test_zero_dim() {
         let buf = Buffer::from(&[1]);
         let tensor = UInt8Tensor::new(buf, None, None, None);
-        assert_eq!(1, tensor.size());
+        assert_eq!(0, tensor.size());
         assert_eq!(None, tensor.shape());
         assert_eq!(None, tensor.names());
         assert_eq!(0, tensor.ndim());
@@ -270,7 +268,7 @@ mod tests {
 
         let buf = Buffer::from(&[1, 2, 2, 2]);
         let tensor = Int32Tensor::new(buf, None, None, None);
-        assert_eq!(1, tensor.size());
+        assert_eq!(0, tensor.size());
         assert_eq!(None, tensor.shape());
         assert_eq!(None, tensor.names());
         assert_eq!(0, tensor.ndim());